THE only difference between the 2 boards are:
1). extrs optical out (the J has only a coax SPDIF out not both like the K+)
2). Extra raid controller with 4 more sata ports. The J has only the chipset native default sata ports, and yes it can raid those the native 250GB chipset ones(
Yes I just got this board, doing great, just waiting on the heatsink fan (long story of collerguys messing up then maybe coming threw) to overclock